Sure. How about BUFFY THE VAMPIRE SLAYER SEASON 8?
The periodical sales for the first 5 issues (from Marc-Oliver Frisch's analysis @ The Beat):
03/2007: Buffy #1 — 109,919 [158,437]
04/2007: Buffy #2 — 96,409 (-12.3%) [132,378]
05/2007: Buffy #3 — 106,634 (+10.6%) [125,078]
06/2007: Buffy #4 — 102,430 (- 3.9%) [117,866]
07/2007: Buffy #5 — 100,830 (- 2.0%) [109,322]
More than 643k copies sold, with a low point of 109k, and an average of 128k
BUFFY THE VAMPIRE SLAYER v1: THE LONG WAY HOME, which contains those five issues (pulled out of the ICv2 charts):
Equals 17,720 copies sold.
BookScan during the last 3 months of 2007 (I don't have '08 data yet): 13025, and given that the first three months are virtually identical to the DM (a diff of all of 182 copies), let's be generous and say it's 19k total through the full six months.
Roughly 37k total in both channels.
(Parenthetically worth mentioning, at a $15.95 cover price, the cost-per-issue is $3.19, vs $2.99 on the periodical)
Now, would a creator rather have a minimum of 109k readers (or an average of 128k), or 37k?
I'm going to go way way way out on a limb and guess it would be the former.
Not that I purposefully picked one of the single most attractive-to-"civilians" properties here, to skew the argument more to "your" side.
Over a 3-5 year period, sure, the book will eventually sell more copies than the periodical, but the real truth is that, outside of a very small percentage of books, most TP collections or OGNs actually have viable sales windows that number in the months, if not weeks -- not years.
If you look at Diamond's newly expanded top *300* book list, you can see BUFFY v1 has slipped down to ~400 copies sold per month now -- maybe a third of its initial velocity. This is simply how books sell, over time!